diff --git a/src/mightypork/rogue/world/tile/Tile.java b/src/mightypork/rogue/world/tile/Tile.java
index ce7b8ae..b3886d3 100644
--- a/src/mightypork/rogue/world/tile/Tile.java
+++ b/src/mightypork/rogue/world/tile/Tile.java
@@ -27,17 +27,15 @@ public abstract class Tile implements IonBinaryHeadless {
 	
 	protected final TileRenderer renderer;
 	
-	public final int id;
-	
-	protected final Stack<Item> items = new Stack<>();
+	public final TileModel model;
 	
 	// temporary flag for map.
 	protected boolean occupied;
 	protected boolean explored;
 	
 	
-	public Tile(int id, TileRenderer renderer) {
-		this.id = id;
+	public Tile(TileModel model, TileRenderer renderer) {
+		this.model = model;
 		this.renderer = renderer;
 	}
 	
@@ -176,6 +174,12 @@ public abstract class Tile implements IonBinaryHeadless {
 	}
 	
 	
+	public final TileModel getModel()
+	{
+		return model;
+	}
+	
+	
 	/**
 	 * Drop item onto this tile
 	 * 
diff --git a/src/mightypork/rogue/world/tile/Tiles.java b/src/mightypork/rogue/world/tile/Tiles.java
index 234856e..f563e87 100644
--- a/src/mightypork/rogue/world/tile/Tiles.java
+++ b/src/mightypork/rogue/world/tile/Tiles.java
@@ -61,9 +61,9 @@ public final class Tiles {
 	
 	public static void saveTile(IonOutput out, Tile tile) throws IOException
 	{
-		out.writeIntByte(tile.id);
+		TileModel model = tile.getModel();
 		
-		TileModel model = get(tile.id);
+		out.writeIntByte(model.id);		
 		model.saveTile(out, tile);
 	}
 
diff --git a/src/mightypork/rogue/world/tile/tiles/DoorTile.java b/src/mightypork/rogue/world/tile/tiles/DoorTile.java
index 5dea905..bfc7202 100644
--- a/src/mightypork/rogue/world/tile/tiles/DoorTile.java
+++ b/src/mightypork/rogue/world/tile/tiles/DoorTile.java
@@ -1,14 +1,16 @@
 package mightypork.rogue.world.tile.tiles;
 
 
+import mightypork.rogue.world.tile.TileModel;
 import mightypork.rogue.world.tile.TileRenderer;
 import mightypork.rogue.world.tile.TileType;
 
 
 public class DoorTile extends SolidTile {
 	
-	public DoorTile(int id, TileRenderer renderer) {
-		super(id, renderer);
+	public DoorTile(TileModel model, TileRenderer renderer)
+	{
+		super(model, renderer);
 	}
 	
 	@Override
diff --git a/src/mightypork/rogue/world/tile/tiles/FloorTile.java b/src/mightypork/rogue/world/tile/tiles/FloorTile.java
index 949623f..af8e57b 100644
--- a/src/mightypork/rogue/world/tile/tiles/FloorTile.java
+++ b/src/mightypork/rogue/world/tile/tiles/FloorTile.java
@@ -1,15 +1,16 @@
 package mightypork.rogue.world.tile.tiles;
 
 
+import mightypork.rogue.world.tile.TileModel;
 import mightypork.rogue.world.tile.TileRenderer;
 import mightypork.rogue.world.tile.TileType;
 
 
 public class FloorTile extends GroundTile {
 	
-	public FloorTile(int id, TileRenderer renderer)
+	public FloorTile(TileModel model, TileRenderer renderer)
 	{
-		super(id, renderer);
+		super(model, renderer);
 	}
 	
 	
diff --git a/src/mightypork/rogue/world/tile/tiles/GroundTile.java b/src/mightypork/rogue/world/tile/tiles/GroundTile.java
index f58ac24..54966f4 100644
--- a/src/mightypork/rogue/world/tile/tiles/GroundTile.java
+++ b/src/mightypork/rogue/world/tile/tiles/GroundTile.java
@@ -2,12 +2,14 @@ package mightypork.rogue.world.tile.tiles;
 
 
 import java.io.IOException;
+import java.util.Stack;
 
 import mightypork.rogue.world.item.Item;
 import mightypork.rogue.world.level.Level;
 import mightypork.rogue.world.level.render.TileRenderContext;
 import mightypork.rogue.world.tile.DroppedItemRenderer;
 import mightypork.rogue.world.tile.Tile;
+import mightypork.rogue.world.tile.TileModel;
 import mightypork.rogue.world.tile.TileRenderer;
 import mightypork.util.files.ion.IonInput;
 import mightypork.util.files.ion.IonOutput;
@@ -17,10 +19,11 @@ public abstract class GroundTile extends Tile {
 	
 	private DroppedItemRenderer itemRenderer = new DroppedItemRenderer();
 	
+	protected final Stack<Item> items = new Stack<>();
 	
-	public GroundTile(int id, TileRenderer renderer)
+	public GroundTile(TileModel model, TileRenderer renderer)
 	{
-		super(id, renderer);
+		super(model, renderer);
 	}
 	
 	
diff --git a/src/mightypork/rogue/world/tile/tiles/LockedDoorTile.java b/src/mightypork/rogue/world/tile/tiles/LockedDoorTile.java
index 7b1ea96..18c9474 100644
--- a/src/mightypork/rogue/world/tile/tiles/LockedDoorTile.java
+++ b/src/mightypork/rogue/world/tile/tiles/LockedDoorTile.java
@@ -3,6 +3,7 @@ package mightypork.rogue.world.tile.tiles;
 
 import java.io.IOException;
 
+import mightypork.rogue.world.tile.TileModel;
 import mightypork.rogue.world.tile.TileRenderer;
 import mightypork.util.files.ion.IonInput;
 import mightypork.util.files.ion.IonOutput;
@@ -13,9 +14,15 @@ public class LockedDoorTile extends DoorTile {
 	public boolean locked = true;
 	
 	
-	public LockedDoorTile(int id, TileRenderer renderer)
+	public LockedDoorTile(TileModel model, TileRenderer renderer)
 	{
-		super(id, renderer);
+		super(model, renderer);
+	}
+	
+	@Override
+	public boolean isWalkable()
+	{
+		return !locked;
 	}
 	
 	
diff --git a/src/mightypork/rogue/world/tile/tiles/NullTile.java b/src/mightypork/rogue/world/tile/tiles/NullTile.java
index 5ad12e1..bbd9dcd 100644
--- a/src/mightypork/rogue/world/tile/tiles/NullTile.java
+++ b/src/mightypork/rogue/world/tile/tiles/NullTile.java
@@ -5,15 +5,16 @@ import mightypork.rogue.world.item.Item;
 import mightypork.rogue.world.level.Level;
 import mightypork.rogue.world.level.render.TileRenderContext;
 import mightypork.rogue.world.tile.Tile;
+import mightypork.rogue.world.tile.TileModel;
 import mightypork.rogue.world.tile.TileRenderer;
 import mightypork.rogue.world.tile.TileType;
 
 
 public class NullTile extends Tile {
 	
-	public NullTile(int id, TileRenderer renderer)
+	public NullTile(TileModel model, TileRenderer renderer)
 	{
-		super(id, renderer);
+		super(model, renderer);
 	}
 	
 	
diff --git a/src/mightypork/rogue/world/tile/tiles/SolidTile.java b/src/mightypork/rogue/world/tile/tiles/SolidTile.java
index 2173c51..3dd5772 100644
--- a/src/mightypork/rogue/world/tile/tiles/SolidTile.java
+++ b/src/mightypork/rogue/world/tile/tiles/SolidTile.java
@@ -2,13 +2,15 @@ package mightypork.rogue.world.tile.tiles;
 
 import mightypork.rogue.world.item.Item;
 import mightypork.rogue.world.tile.Tile;
+import mightypork.rogue.world.tile.TileModel;
 import mightypork.rogue.world.tile.TileRenderer;
 
 
 public abstract class SolidTile extends Tile {
 
-	public SolidTile(int id, TileRenderer renderer) {
-		super(id, renderer);
+	public SolidTile(TileModel model, TileRenderer renderer)
+	{
+		super(model, renderer);
 	}
 	
 	@Override
diff --git a/src/mightypork/rogue/world/tile/tiles/WallTile.java b/src/mightypork/rogue/world/tile/tiles/WallTile.java
index 7c3be10..daac8a2 100644
--- a/src/mightypork/rogue/world/tile/tiles/WallTile.java
+++ b/src/mightypork/rogue/world/tile/tiles/WallTile.java
@@ -1,14 +1,15 @@
 package mightypork.rogue.world.tile.tiles;
 
+import mightypork.rogue.world.tile.TileModel;
 import mightypork.rogue.world.tile.TileRenderer;
 import mightypork.rogue.world.tile.TileType;
 
 
 public class WallTile extends SolidTile {
 
-	public WallTile(int id, TileRenderer renderer)
+	public WallTile(TileModel model, TileRenderer renderer)
 	{
-		super(id, renderer);
+		super(model, renderer);
 	}
 
 	@Override